To check the payment status of a Purchase Order, find the corresponding Bill number:


In the Purchase Order, go to 'Related Records'. If a Bill has been created for the Purchase Order, it will display under the 'Receipts & Bills' tab:



Click on the corresponding date of the Bill to be taken to the Bill page. 


At the top, the Bill status will either be 'Paid in Full' or 'Open'. 



If the Bill is paid in full, the exact payment date can be determined by going to 'Related Records' and then 'Payments'.